Polythiophens and Related Systems

Polythiophens and Related Systems.— Two groups have prepared compounds containing two thiophen rings fused to medium-sized carbocycles. At the University 

Tsuchiya, M. Enkaku, J. Kurita, and H. Sawanishi, Chem. Pharm. Bull., 1979,27,2183. 

4 -bibenzo[6]thiophen (52), has been made. It is isoelectronic with perylene and, indeed, has similar physical and chemical properties.  

The tetrathiophens (53) and (54) have been synthesized, in moderate yield, by the reaction of dibromobithiophens with butyl-lithium, followed by oxidative coupling with ferric or cupric chloride.  

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